This work presents an ultra-high gain quadratic boost (UHGQB) converter for photovoltaic applications with a detailed operational and steady-state analysis. Further, the comparative analysis of the UHGQB converter with existing converters suggests that the UHGQB converter performs better in terms of total component count, TVS, TCS, SDP rating, volume of inductors and capacitors, and efficiency. In addition, MATLAB-based simulations are conducted for a 650 V, 1 kW, and 50 kHz system. The open and closed loop simulation results validated the satisfactory steady-state and dynamic performance of the UHGQB converter. Furthermore, the efficiency analysis was carried out and the UHGQB converter was found to have the highest efficiency of 95.2 %. Therefore, the proposed UHGQB converter can be adopted for photovoltaic systems as well as other high-voltage applications.